ACL Bearings 1B1442HX-STD Race Series Connecting Rod Bearing Single Standard Size +0.001" Extra Clearance

The ACL Bearings 1B1442HX-STD is a single Race Series high-performance connecting rod bearing (one journal set, two half-shells) designed for standard crankshaft journals with an extra 0.001" oil clearance over the standard H-STD specification. This is the HX variant of ACL's Race Series line, purpose-built for engine builders who need additional oil film clearance for modified or high-performance applications.

The "HX" designation means each bearing half is 0.0005" thinner than the corresponding H-STD shell, resulting in 0.001" of additional total oil clearance on a standard-size journal — a popular choice for performance and forced-induction builds where increased lubrication flow to the rod journal is critical.

Key Features:

• +0.001" Extra Oil Clearance — HX suffix indicates shells are 0.0005" thinner per half versus H-STD, providing 0.001" more total clearance on a standard journal
• Standard Size (STD) — Designed for use with unground, factory-specification crankshaft rod journals
• High-Strength Overlay Plate — Reduced-thickness overlay for improved fatigue resistance under high-load conditions
• Hardened Steel Backing — Improves structural support of the bearing lining and aids retention in the connecting rod housing
• Increased Crush — Enhanced bearing retention to prevent shell movement during operation
• No Flash Plating on Back — Bare steel backing promotes better heat transfer and maximizes grip between the shell and housing bore
• Increased Eccentricity — Compensates for bore distortion at high RPM and assists in the formation of a hydrodynamic oil film
• Single Bearing (1B Prefix) — Supplied as one journal's worth of shells (upper + lower half); ideal for replacing a single journal or custom mixing clearances

ACL Race Series bearings are a trusted choice among professional engine builders for both street performance and full competition applications. The ability to mix HX-STD and H-STD shells on the same journal allows precise oil clearance tuning in 0.0005" increments — a technique widely used in high-performance engine building.